A finite conjugate imaging system was disclosed in U.S. patent application Ser. No. 676,295 as a subsystem of a catadioptric imaging system that is color-corrected at five wavelengths (i.e., which brings paraxial marginal rays to a common focus at five discrete wavelengths). Accordingly, the design form of the finite conjugate imaging system, functioning as a subsystem, was optimized in that particular application to correct for chromatic aberrations, monochromatic aberrations, and chromatic variations of the monochromatic aberrations of the overall catadioptric imaging system of which the finite conjugate imaging system was a part.
The finite conjugate imaging system that was described as a subsystem in U.S. patent application Ser. No. 676,295 could also function independently as a relay lens. However, to function as a useful microscope objective, the finite conjugate imaging system would have to be re-designed and optimized to correct for chromatic aberrations, monochromatic aberrations and chromatic variations of the monochromatic aberrations in order to operate at higher magnification with a higher numerical aperture.
It is an object of the present invention to re-optimize the design form of the finite conjugate imaging system described in U.S. patent application Ser. No. 676,295 for use independently as a microscope objective. In particular, the design form of that finite conjugate imaging system has been re-optimized according to the present invention in order to provide 10X magnification with a numerical aperture of 0.25, while retaining color correction at five discrete wavelengths with minimal residual aberrations.